A surface high far N of the area will maintain NE surface flow over the main Hawaiian Islands. These NE winds will continue to push showery low clouds from the trailing end of a front over the islands. MVFR ceilings will likely be extensive enough to require AIRMET SIERRA for MTN OBSC to remain up throughout the night for NE sections of most islands.

A sharp short-wave trough aloft is enhancing shower activity over the islands today. Isolated thunderstorms have already developed over the Big Island interior and waters west of the Big Island and south of Maui. Thunderstorm activity will likely continue into the evening hours but taper off after midnight.